Study Guide: The Coordinate Plane

These web-based activities were developed, during summer sessions from 1997 through 1999, by students at Mainland High School, located in Daytona Beach, FL. As part of Mainland's CCTT grant, the students were given permission by the book's publisher to convert the ancillary materials of the County's adopted Algebra 1 textbook (Glencoe Algebra 1 — ISBN: 9780028253282) into html format.

In the diagram to the right, the two perpendicular line are called the x-axis and the y-axis. These two lines divide the coordinate plane into Quadrants I, II, III, and IV. The point where the two axes intersect is called the origin. The origin is represented by the ordered pair (0,0). Every other point in the coordinate plane is also represented by the an ordered pair of numbers. The ordered pair for point Q is (5, −4). We say that 5 is the x-coordinate of Q and −4 is the y-coordinate of Q.
Example: Write the ordered pair for point R above. The x-coordinate is 0 and the y-coordinate is 4. thus the ordered pair for R is (0, 4).
To graph any ordered pair (x, y) begin at the origin. Move left or right x units. From there, move up or down y units. Draw a dot at that point.
Directions: Plot each point on the coordinate plane at the right.
Directions: Write the ordered pair for each point shown at the right. Name the Quadrant in which each Point is located. G H I J